Pollutant Concentrations

Air quality readings will be available hourly from 7am to 11pm. Air quality readings from 12am to 6am will be made available at 7am on the same day.

Readings on 15 Nov 2014

View reading for:

Region

24-hr Sulphur dioxide(µg/m3)

24-hr PM10(µg/m3)

1-hr Nitrogen dioxide(µg/m3)a

8-hr Ozone(µg/m3)

8-hr Carbon monoxide(mg/m3)

24-hr PM2.5(µg/m3)

North

7(5)

17(17)

35(-)

16(7)

0.4(4)

10(40)

South

12(7)

18(18)

28(-)

24(10)

0.5(5)

9(36)

East

4(3)

15(15)

20(-)

36(15)

0.4(4)

9(38)

West

3(2)

14(14)

7(-)

44(18)

0.6(6)

7(29)

Central

6(4)

15(15)

40(-)

46(20)

0.5(5)

8(34)

1-hr PM2.5 (µg/m3)b Readings on 14 Nov 2014

View reading for:

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

North

5

11

7

6

3

6

6

12

14

6

10

10

South

7

6

7

7

2

4

2

5

10

10

10

13

East

10

12

9

10

10

3

4

4

12

6

11

6

West

4

7

3

4

4

3

5

9

8

6

10

10

Central

13

8

6

5

6

4

3

4

10

7

7

8

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

North

7

9

11

12

14

10

16

7

13

14

19

5

South

11

16

13

16

16

16

11

6

5

5

7

3

East

6

11

15

8

12

9

13

13

6

10

11

10

West

8

6

12

9

9

6

10

5

6

10

9

4

Central

10

9

9

8

12

11

13

11

9

7

12

6

Note:a Sub-index for nitrogen dioxide is reported only when the 1-hr concentration equals or exceeds 1130 µg/m3.

b There is no sub-index for 1-hr PM2.5.

3-hr PSI Readings from 1am to 12am on
14 Nov 2014

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

3-hr PSI

50

45

32

30

24

21

18

21

30

34

38

36

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

3-hr PSI

38

39

43

45

48

46

49

44

40

35

40

37

Hourly updates of 3-hr PSI readings are provided from 7am to 11pm. The 3-hr PSI readings from 12am to 6am will be made available at 7am on the same day. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.